The major goal of this research is for the principal investigator to gain experience in fluorescence activated cell sorting and in molecular techniques so that these tools can be applied to future research to define the mechanism of alcohol's influence on the immune response. To accomplish these goals, the hypothesis that alcohol enhances expression of class I histocompatibility antigens and that this contributes to decreased natural killer cell activity will be tested. Natural killer cell numbers, activity and class I H-2 antigen expression in normal and nude C57BL/10 and congenic C57BL/10A, ethanol-consuming, pair-fed and control mice will be examined. Natural killer cell activity will be studied using a standard chromium release assay. NK cell numbers will be examined for expression of asialo-GM1 and NK 1.1 surface markers on spleen lymphocytes in ethanol-consuming and control mice using a fluorescence activated cell sorter. Cells expressing the NK 1.1 surface marker will be sorted and mRNA levels for class I antigens will be analyzed. These experiments will determine if increased class I antigen expression induced by alcohol correlates with increased mRNA levels. This correlation will insure that increased expression of class I antigens is not due to the effect of ethanol on the cell membrane.